Vocal counter circuit



Feb. 4, 1969 J. R. DE PRIEST VOCAL COUNTER CIRCUIT Sheet Original Filed Oct. 24, 1961 W ATTORNEYS Feb. 4, 19

J. R. DE PRIEST VOCAL COUNTER CIRCUIT Original Filed Oct. 24, 1961 Sheet 2 of 6 Tha 4.

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Y E 7b P4060 Med/7S #y Tra/vs- Message Geri. *E Sg/M/ v Gen. m//f Re/ys. ge/ep/yane I I I I I+ aff/,oaf Messaye Q76 Y @buf/fel I//PU/ 76. SW//C/'g Mea/:9&2 I Message 77 I Meaps Se/@c/'on I n -Q pe/gys 05116 I! 6,0) L C'OI/er 0 Mea/7s #N z U9 F b V Meg/7S JPG/Q15 Ou/pa/ S/ep/hy -4--J gn/#r E Mevr/'5 2 VOICE TIME INTERVAI. CHANNEL IT 2T 4T 5T IGT 7T 8T 9T IOT IIT I2T SEA- RIL- RICE- GEOR- HOT Y A BOARD ROAD BORO GIA FIRST BOX LEFT SIDE ZERO ZERO ZERO B SECOND RIGHT ONE ONE ONE C THIRD TWO TWO TWO D FOURTH THREE THREE THREE E FOUR FOUR FOUR F FIVE FIVE FIVE G SIX SIX SIX H SEVENSEVEN SEVEN J EIGHT EIGHT EIGHT K NINE NINE NINE IA ON OFF OFF ON OFF ON OFF ON OFF ON OFF d 5 I 0 FF @I OEE O FE @L QN QF QF F O N O N QF LPEQI QIL-- 9N. @L O N ffl OEE PE". Ofi 9N I D OFF OFF OFF OFF OFF OFF ON ON ON ON ON INVENTOR JOSEPH ROY De P12/55T ATTOR NEYS Feb. 4, 1969 J. R. DE PRIEST vVOCAL COUNTER CIRCUIT Original Filed Oct. 24, 1961 'ofe Sheet f 1 ATToRNraYsl Sheet 4 of@ Feb. 4, 1969 J. R. DE: PRIEST VOCAL COUNTER CIRCUIT original Filed oct. 24, 1961 x fl,

dass/JH /20 Y De PQ/Es BY V tg W ATTORNEYS Feb. 4, 1969 J. R. DE PRIEST 3,426,181

VOCAL COUNTER CIRCUIT Original Filed Oct. 24, 1961 Sheet 5 of 6 I 773g Upg 3% E doSEP/l Rayne PR/rr I 1::1' BY v W5 ATTORNEYS Feb. 4, 1969 J. RDE PRnEs-r 3,426,181

VOCAL COUNTER CIRCUIT Original Filed Oct. 24, 1961 Sheet 6 e +V .(75 L4 i l rp u uw* p L ff u WV @P23 we; ma? we?? lNvENToR JOSEPH ROY 0e PR/sT United States Patent O 3,426,181 VOCAL COUNTER CIRCUIT Joseph Roy De Priest, Richmond, Va., assigner, by mesne assignments, to Servo Corporation of America, Hicksville, N.Y., a corporation of New York Continuation of application Ser. No. 147,317, Oct. 24, 1961, now Patent No. 3,226,540, dated Dec. 28, 1965. This application May 18, 1965, Ser. No. 456,698 U.S. Cl. 23S-92 6 Claims Int. Cl. G06f 7/48; 606g 7/02 ABSTRACT F THE DISCLOSURE A vocal counter circuit for automatically vocalizing the axle position of an overheated journal box in a passing train characterized by a message generator having a plurality of channels equal in number to at least the numeric base of the axle counter. Each channel is broken into discrete time zones, each zone representing a vocal digit. The channels are Icycled in common and selected channels are sequentially coupled to the output on a time sequence basis.

This invention is a continuation of my co-pending application Ser. No. 147,317, tiled Oct. 24, 1961, now U.S. Patent No. 3,226,540. It relates to a novel vocal counter circuit which inter alia is adaptable to an improved hot box detector circuit of the type which is mounted alongside a railroad track to automatically detect overheated journal boxes in passing trains and to produce an alarm signal indicating the presence and location of the overheated journal boxes. The invention is characterized by a novel vocal alarm circuit which reports the presence and loca-tion of the hot boxes to the crew of a passing train and to the train dispatcher by means of an uncoded verbal message which `can be understood by any listener.

Hot box detector alarm circuits per se are old in the art, but in the past it has been the practice to signal the presence of a hot box by means of an alarm bell or light and to indicate the location of the hot box visually on a recording :graph or counter which was driven by the hot box detector circuit. In some installations the alarm light and counter were located near the hot box detector site and were operated automatically by the hot box detector circuit. In these installations the train crew would watch for the alarm light, and when it ashed on they would stop the train, go to the trackside recorder or counter to determine the location of the hot box, and then repair the hot box. In other installations the alarm light and counter were located in the train dispatchers otice, and the dispatcher would signal the train to stop when he received a hot box alarm signal. In these installations the train crew would stop the train on receipt of the dispatchers signal, call the dispatcher from a trackside telephone to determine the location of the hot box, and then -repair the hot box.

Although these prior art hot box detector alarm circuits operated satisfactorily in some applications, it is desirable in many applications to report the location of the hot box directly to the train crew immediately after the hot box has been detected so that they will know the location of the hot box before the train is stopped. It is also desirable to simultaneously report the presence and location of the hot box to the train dispatcher so that he will be advised of the impending train stoppage, and to make both reports in an uncoded verbal message which can be understood by any listener.

Accordingly, one object of this invention is to provide a hot box detector alarm circuit which reports the presence and location of hot boxes directly to the crew of a passing train.

ICC

Another object of this invention is to provide a hot box detector alarm circuit which reports the presence and location of hot boxes directly to the crew of a passing train immediately after the location of the hot boxes has been determined by the hot box detector circuit.

An additional object of this invention is to provide a hot box detector alarm circuit which simultaneously reports hot boxes to the crew of a passing train and to the train dispatcher.

A further object of this invention is to provide a hot box detector alarm circuit which indicates the presence and location of hot boxes by means of an uncoded verbal message which can be conveniently transmitted to the crew of a passing train via a low power voice radio link and to the train dispatcher via existing trackside telephone wires.

Another object of this invention is to provide a hot box detector alarm lcircuit which signals the presence and location of hot boxes by means of uncoded verbal messages which can be understood by any listener.

Yet another object of this invention is to provide a hot box detector alarm circuit which is more effective than those heretofore known in the art.

Other objects and advantages of this invention will become apparent to those skilled in the art from the following description of one specilic embodiment thereof, as illustrated in the attached figures, in which:

FIG. 1 is a perspective view of a section of railroad track containing a pair of heat responsive detector elements and a plurality of wheel pick-up devices mounted therealong;

IFIG. 2 is a side view of the railroad track shown in FIG. 1 indicating the placement of the heat responsive detectors and wheel pick-up devices with respect to a standard journal box;

FIG. 3 is a partial schematic diagram of one illustrative hot box detector alarm circuit of this invention;

FIG. 4 is a more detailed block diagram of the vocal readout means indicated in FIG. 3;

FIG. 5 is a chart showing one suitable vocal output program and synchronizing system for the message generator of FIG. 4;

FIG. 6 is a partial schematic diagram of one suitable message generator and synchronizing system which are programmed in accordance with the chart of FIG. 5;

FIG. 7 is a partial schematic diagram of one suitable hot box counter circuit;

FIG. 8 is a partial schematic diagram of one suitable vocal output circuit which can be used in connection with the circuits of FIGS. 6 and 7; and

FIG. 9 is a partial schematic diagram of an output stepping motor circuit which can be used in the circuit of FIG. 8.

This invention is an improvement over prior art hot box detector alarm circuits such as disclosed, for example, in U.S. Patent No. 2,963,575, which was issued on Dec. 6, 1960, to William M. Pelino and Harold Remz for a Hot Box Detector Alarm Circuit. Although this invention differs radically from the Pelino device in the alarm portions of its circuitry, it utilizes the same basic hot box detector circuits disclosed in the above noted Pelino patent, and FIGS. 1, 2 and the left hand portion of FIG. 3 are therefore copied from FIGS. 1, 2, and 3 of the Pelino patent.

Referring to FIGS. l, 2, and 3, this invention is shown in application to plural detector units 10-11 xedly mounted alongside the right of way and on opposite sides of a gi-ven section of longitudinally extending track, comprising rails 12,-13. The detector units 10-11 may be exact duplicates of each other, and therefore in FIG. 3 the important parts of the detector 10 are shown in greater detail, whereas those within the detector 11 are merely schematically indicated by a block designation. -Each of the detector units may include an active heat-responsive cell 14, such as a so-called thermistor fiake, shown connected in a bridge circiut employing a second or compensator cell 15, shielded by means 16 from incident radiation and therefore responsive only to ambient temperature.

As indicated, the cells 14-15 are placed in a bridge circuit, the arms of which are shown oppositely polarized, as by application of positive biasing Voltage to the outer terminal of cell 15 and negative biasing voltage to the outer terminal of the cell element 14. Bridge output is available in line 17 to pre-amplifier means 18, which may be contained within the housing of the detector unit 10. As indicated, similar components are provided at detector and amplifier means 11.

At detector unit 10, infrared-transmitting optics, such as the lens 19, is so mounted within the detector housing 20 as to image the active cell 14 on a generally upwardly inclined axis 21 (having an elevation angle a), and preferably focused at the horizontal plane of passing journal boxes, such as the box 22 (FIG. 2) for freight-car rolling stock; detector 11 has a similarly inclined response axis 21. A full discussion of orientation in the manner indicated for the axis 21 in reference to journal boxes, as at 22, is contained in U.S. Patents No. 2,880,309 and Re. 24,983 so that further detail on that subject is not presented herein. The imaging axis 21 is shown to pass through a localized opening 23 in the housing 20, and shutter means 24 between the lens 19 and the housing opening 23 provides a mechanical protection for the lens element and other internal parts of the system, as long as no trains are passing. The shutter 24 is merely schematically designated in FIG. 3 and may comprise a simple blade, actuated by solenoid means 25, as will be understood.

As indicated generally above, this detector circuit relies importantly on the operation of a gating means 26 accommodating the separate outputs 27-28 of the respective detectors 10-11 and assuring that said detectors effectively look only at journal boxes, that is, to the exclusion of all other matter passing the field of View of the respective detector-response axis. To operate the gate, this detector circuit uses electromagnetic wheel trips which may be and preferably are of the variety disclosed in U.S. Patent No. 2,973,430, wherein a polarized magnetic air gap is established in the path of oncoming wheel flanges so that the passage of each wheel flange automatically develops a suitably characterized pulse, clearly identifying the instant at which each wheel center passes a particular point along the track.

The wheel-trip location is so related to the placement of the detectors 10-11 and their respective responsive axes 20-2'1 that gating occurs only when the axes 20-21' are imaged on opposed journal boxes for the same axle. In the form shown, two such Wheel trips (labeled B and C in FIGS. l, 2 and 3) are employed, the effective spacing D between said trips being determined in the manner specified in greater detail in said U.S. Patent No. Re. 24,983, whereby at the instant for which the phantom outline 29' for a particular truck wheel 29 is symmetrically positioned over the trip B, the optical alignment 21 of the detector 10 is barely tangential to the bottom of the journal box 22 identified at 22. An instant later, the wheel 29 and box 22 have moved to the position shown in solid outline in FIG. 2, at which time the Wheel center is symmetrically positioned with respect to the trip C, and at this time the response axis 21 is just grazing the top corner of the journal box 22. Thus, the gated interval determined by pulses from pickups B and C may be employed first to turn on and then to turn off the gating function at 26, determining response only to heat radiated by the journal box 22, regardless of the speed of the passing wheel 29. Ordinarily, for a viewing axis 21 or 21 having an elevation of the order of above the horizontal, and fOr Observation of conventional freight-car journals 22, the preferred effective spacing D between the pickups B and C is of the order of 40 inches.

As also explained in said U.S. Patent No. Re. 24,983, the shutter means (24) is actuated to expose the optics on the alignments 21-21 as long as any train is passing the installation. For this purpose, we show the employment of an additional wheel trip identified at A in the drawings. The pickup or trip A may be of the same nature as employed at B and C, and for the situation depicted in FIG. 2 (wherein the aspect of viewing on the passing rolling stock is for a train going away from the detector; in other words, trailing-aspect viewing), the pickup A is preferably spaced ahead of the pickups B and C, as shown. Output pulses from the pickup A are shown to be passed to a relatively longtime constant storage circuit 30, the output of which will be a voltage sufficient to hold open the shutters 24 of the respective detectors `10-'11 as long as pulses are generated by the pickup A, and even for the slowest speed trains, down to, say, five miles an hour.

As indicated generally above, this detector system automatically discriminates against locomotives, passenger cars and other railroad rolling stock which is not of standard freight-car wheelbase dimensions. Freight car truck wheelbases are standardized at five and one-half feet, and this detector circuit makes use of the fact that this wheelbase is not encountered in any other type of rolling stock, including locomotives and passenger cars. In FIG. 3, the outputs of both pickups A and B are fed to a coincidence circuit 31 effective to pass in the output line 32 a wheeltrip pulse only when the two wheels of a given truck 33 simultaneously actuate the trips or pickups A and B. In FIG. 2, this condition is illustrated in lightly dashed outline, the wheels being identified at 29'34 for the truck 33, and it will be seen that the preferred spacing, of course, for the trips A-B is the aforesaid wheelbase to be selected, namely, tive and one-half feet, being the wheelbase for trucks of standard American freight-car rolling stock.

Coincidence pulses derived in line 32 are shown fed to a storage circuit 35 which is again of the long-time constant variety, as disclosed at 30, and serve to operate enabling means such as a relay 36 for conditioning the gate 26 for operation. In other words, the function of the pickups A and B in combination with the circuits 31- 35-36 is to prevent operation of the gate 26 until such time as the first freight-car truck is encountered, and yet to maintain the gate suitably conditioned (once it has been enabled) for the full passage of the freight cars in the train even for slow trains. This means, of course, that for the usual situation in which a locomotive is pulling a train, no locomotive trucks or wheel arrangements will be effective to enable the gate 26, inasmuch as the standard freight-car wheelbase occurs only for freighto cars and not for locomotives; it may also be observed that the standard freight-car Wheelbase (5l/2 feet) is not encountered in passenger rolling stock, so that here too, the gate 26 is not enabled (and, therefore, cannot be opened) for any given train until such time as the first freight-car truck is detected by the coincidence circuit 31.

It so happens that for the particular wheel trip which we have employed in our work to date, the identifying pulse marking the instant passage of a wheel center past a given location on a track is relatively short compared to the time within which the whole journal box 22 is viewable, namely, the time taken for a train to pass the distance D between pickups B and C. Also, it so happens that, because of axial and other play in the mounting of axles, wheels and trucks, a given freight-car axle will not at all times necessarily be perfectly aligned perpendicular to the gage line of the track. This means that a heat detection pulse derived upon exposure for the detector 10 along the axis 2'1 may be slightly differently timed (or out of phase) with respect to the corresponding pulse derived for exposure along the axis 21. Thus any difference evaluation of slightly de-phased pulses of this character could result in failure to obtain a true differential evaluation.

In accordance with this detector circuit, however, any such phase error due to misalignment of the axle with respect to the track is avoided by using the gated interval as the period during which any heat signals developed by detectors -11 will be stored or integrated. Thus, if the heat signal for one detector 10 is developed relatively early in the gated interval, compared to the time of development of the heat signal for the other detector 11, the function and effect of the storage means will be to present stored signals of magnitudies reflecting the observed heat signal, but without any phase displacement; thus a simultaneous readeout of the stored information may result in true differential evaluation.

In the form shown in FIG. 3, such storage means comprises two resistance-capacitance networks 40-41 and 42-43 charged by diodes 44-45 connected respectively to two outputs of the gate 26, the output 46 presenting gated signals of intelligence developed only by the cell 14 within the detector 10, and the output 47 similarly presenting gated signals originating at the detector 11. The time constant for charging the capacitors 41-43 is relatively short, that is, in the forward direction for the diodes 44-'45.

In the reverse direction, Iof course, the diodes 44-45 block, and therefore the charge is held on each of the capacitors 41-43 until discharge upon read-out.

Read-out is initiated by the closure of relay contacts 51 of relay 52, which is actuated by the output of wheel pickup C. Therefore, once the wheel 29 has traversed the distance D between pickups -B and C, the integrated charges at 41-43 will be diierentially evaluated, -upon transient closure of relay 51 at the instant at which wheel 29 is shown in solid outline in FIG. 2. If journal box conditions are normal, the heat observed on the axis 21 will be substantially the same as that observed on the axis 21', and the charges at 41 and 43 will be essentially the same, which means that the voltage drop across the halves of vdivided potentiometer 48 will be approximately equal. If the heat observed on one axis exceeds the heat observed on the other axis, however, the voltage across the corresponding lhalf of potentiometer 48 will exceed the voltage across the other half thereof by an amount proportional to the heat difference. When this voltage dilerence exceeds a predetermined value, thyratron 55 or '56 will be momentarily :tired to indicate the presence of a hot box on the right or left side of the train. The `tiring threshold of the thyratrons is set by potentiometers 61 and 62, as explained more fully in said IU.S. Patent No. 2,963,575. This produces a momentary closure of relay RH or LH, whose contacts initiate a counting operation via input stepping relay means 71, which also receives contact closures from relay TP, which is energized as'long as a train is passing the detector unit, and relay AC, which is energized momentarily for each axle that passes the hot lbox detector.

Except for relays TP, LH, RH, and AC, the circuit as thus far described is substantially identical with the prior art hot box detector circuits, and applicant does not allege any novelty for the above described structural elements except as they interact with the novel units of the circuit, which are disclosed in the right hand portion of FIG. 3 and in FIGS. 4 through 9. Referring to the right hand portion of FIG. 3, input stepping relay means 71 drives a plurality of counter means 1 through N each of which has a left-right (L-R) relay associated with it. Stepping relay means 71 gates the axle count pulses from relay AC into each counter as soon as a hot box is indicated by the closure of relay LH or RH, and stores the left-right information in the corresponding L-R relays. Counter means #l is actuated for the yiirst hot box, counter means #2 for the second hot box, and so on. After the counters have started, they continue to count each axle until the end of the train has passed the detector elements, which is indicated by the de-energization of relay TP. At that time, counter #l will contain the number of axles between the first hot box and the end -of the train, counter #2 will contain the number of axles between the second hot box and the end of the train, and so on. Vocal readout means 72 then examines the contents of each counter in sequence, translates the contents thereor` into a verbal message, and transmits the verbal message to the train crew via a low power radio transmitter 73 and to the train dispatcher via existing trackside telephone lines 74. Vocal readout means 72 automatically resets al1 of the counter circuits after the readout operation has been completed and returns the circuit to its original condition for the next train.

FIG. 4 shows a more detailed block diagram of vocal readout means 72. The novel hot box alarm circuit of this invention is based on a vocal output message generator 75, iwhich is adapted to produce a plurality of verbal output signals including words and numbers, and on output message selection logic 76, which switches the verbal output signals onto an output conductor 77 in time sequence to produce a substantially continuous output message indicating the presence of an abnormally hot journal box and the total number of axles between the hot journal box and the end of the train. This switching is performed via output message switching means 78. The operation of message selection logic 76 is coordinated with the operation of message generator 75 by means of a sync signal generator 79 and output timing means 80, which produce time inter-val signals correlated with the output word and number signals of message generator 75. Output timing means 80 is also coupled to output stepping switch means 81, which activates counter means 1 through N in time sequence to report the presence and location of each hot box in turn. Output stepping switch means 81, of course, does not switch from one counter to the next until one full output message has been completed.

The operation of the vocal readout means shown in FIG. 4 can be more clearly explained by disclosing several specic circuits which are adapted to be used therein. FIGS. 5 and 6 illustrate one suitable circuit arrangement for vocal output message generator 75, sync signal generator 79, output timing means 80, and output message switching means 78. As shown in FIG. 6, this particular vocal output message generator comprises a multiple channel tape recorder 82 which contains message output channels A through K and a synchronizing channel S1. Channels A through K of tape recorder 80 contain recordings of verbal word and number signals .as indicatedin chart 5. Each channel of the tape recorder is divided into twelve time intervals lT through 12T by means of frequency coded synchronizing signals recorded on channel S. Each time interval is defined by a particular combination of four frequencies A through D which are recorded on the synchronizing channel by means of an input winding S1 and are picked up by an output winding S2 whenever the tape recorder is operated. It will be understood, of course, that every output channel of tape recorder 82 operates simultaneously and in synchronism when the tape recorder is activated. In general, the composite output message of this particular circuit .arrangement is derived by switching the appropriate tape channel onto output conductor 77 inthe proper time interval to produce the desired output message. For example, if output channel A is continuously connected to output conductor 77, the output message will be Seaboard Railroad, Riceboro, Ga., rst hot box, left side, zero zero zero. If channel B is switched on in time interval 5T in place of channel A, the word second will be substituted for the word lirst." The other possible combinations of output -messages will be readily apparent to those skilled in the art from the chart of FIG. 5.

The sync signals for this particular embodiment of the invention are derived from frequency detector circuits 83 through 86, each of which activates a corresponding output relay AF through DF when the corresponding frequency is present on channel S of the tape recorder. The contact closures of relays AF, BF, CF, and DF are used to activate time interval relays lT through 12T to dene the critical time interval periods. It will be noted in FIG. 6 that no relays are provided for time intervals 2T through 4T in this particular embodiment of the invention, since the first four time intervals are used as a unit to identify the geographical location of the particular hot box detector installation, which in this example is located on the Seaboard Railroad at Riceboro, Ga. It is necessary, however, to have positive indications for time intervals 5T through llT since these channels are used in this case to identify the number and location of the hot boxes. The relay contact networks that control relays 1T through 12T are arranged to activate these relays in the corresponding time interval shown in the chart of FIG. 5. For example, in time interval 1T, frequency A is on and frequencies B C, and D are off. This means that relay AF will be energized in time interval 1T and that relays BF, CF, and DF will be de-energized. Relay 1T will therefore ybe energized through normally closed contacts DF1, normally open contacts AF1, normally closed contacts CF1, and normally closed contacts BF2. All of the other time interval relays will be de-energized under these conditions, as will be evident from an inspection of their corresponding relay contact inputs.

Tape recorder 82 is energized by relay OP, which connects power source 87 to tape recorder 82 and to transmitter 73, and which connects output conductor 77 to the transmitter and to the telephone line. Relay OP is energized by contacts TF1 of relay TP as soon as the train starts to pass the hot box detector. When relay OP is energized it seals itself closed through contacts OP1 which are coupled to +V through contacts TD1 and 12T1. Relay TD is a time delay relay which when energized picks up its contact after three minutes (i.e. three minutes after voltage is applied thereto by contacts TP1). It can be seen therefore that time delay relay TD will pick up contact TD1 three minutes after the end of the train has passed the hot box detector and that relay OP will consequently be de-energized at the start of the next 12T time interval.

Each channel of tape recorder 82 contains a closed loop of tape, and al1 of the loops are driven continuously in synchronism as long .as power is applied to the tape recorder. Therefore, the tape recorder will continuously recycle through the program shown in FIG. 5 as long as relay OP is operated. While the train is passing, however, the output message is limited to the phrase Seaboard Railroad, Riceboro, Ga. which identiies the geographical location of the hot box detector and gives notice that it is in operation. After the end of the train has passed, as evidenced by the de-energization of relay TP, the hot box identification will be added to this message, and the hot box identification will be repeated until the circiut is turned oif by time delay relay TD. The exact method by which this is done will be more apparent from the circuits of FIG. 7 and FIG. 8, which show one suitable counter means, one suitable output stepping switch means, and one suitable output message selection logic which can be used in connection with the circuit of FIG. 6.

Referring to FIG. 7, one suitable counter means comprises three stepping switchs SIA through SIC which are driven by a counter stepping circuit 88. Counter stepping circuit 88 can -be 'any suitable vstepping switch motor circuit which advances switch SIA by one unit for each axle count input pulse and which advances switch SIB by one unit for each ten units of switch SIA and which advances switch SIC by one unit for each ten units of switch SIB. Counter stepping circuit 88 is normally disabled but receives an enable signal from input stepping relay means 71 when the rst hot box occurs. At the same time a right hot box or left hot box signal is applied to relays RR1 and LRI from input stepping relay means 71. These signals are voltages which energize the -lll corresponding relay, which then seals itself closed and remains closed as long as the operating relay OP remains energized. After the counter stepping circuit 88 has been ena-bled, it will begin to count axle input pulses and continue until the end of the train passes, thus counting the number of axles between the corresponding hot box and the end of the train. This axle count will, of course, -be represented by the position of the stepping switches, with switch SIA representing the units digit of the total count, and switch SIB representing the tens digit, and switch SIC representing the hundreds digit. These numbers are read out in sequence by applying an output enable voltage to the arm of the stepping switches through timing relay.

contacts 9T1, I0T1, and 11T1. Referring to the chart of FIG. 5, it will be seen that time interval 9T corresponds to the hundreds digit of the axle count, and that time interval 10T corresponds to the tens digit, and that time interval 11T corresponds to the units digit. When a voltage is applied to the arm of any of the stepping switches, it is transmitted to one of ten output conductors 0 through 9, which are in turn coupled to output bus conductors as will be described later in connection with FIG. 8.

Each of the counter means l through N in FIGS. 3 and 4 and their corresponding L-:R relays can comprise a stepping switch circuit such as shown in FIG. 7, and each of these counter means will be enabled in turn by input stepping relay means 71 as hot boxes are detected by the detector portion of the circuit. Input stepping relay means 71 can be any suitable relay means for enabling the counter stepping circuit in turn and applying the right or left hot box signals to the associated L-R relays. One circuit of this general type is disclosed in FIG. 4 of the above noted U.S. Patent No. 2,963,575. This particular circuit is designed to operate only from one of the thyrar tron tubes, but it will be apparent that the circuit can be adapted to operate from both of the thyratron tubes by simply forming an OR circuit with the contacts of relays LH and RH and driving the stepping relays from the OR circuit instead of from one of the thyratrons. It will also be apparent that the same basic stepping relay circuit can be used to switch in sequence to the L-R relays, which are not shown in FIG. 3 of said patent. In addition to the above described relay stepping circuit, there are many other suitable relay stepping circuits which can be used to perform the above described functions, as will be apparent to those skilled in the art, and any suitable circuit can be used which enables counter means l through N in sequence in response to the hot box indication and energizes the corresponding left or right relays to indicate the transverse location of the corresponding hot box.

When the end of the train has passed the hot box detector, counter means 1 through 4 will contain the axle count for their corresponding hot boxes and these axle counts are then read out in sequence due to the action of the output stepping motor circuit 89 (FIG. 8) and output stepping switches SOA, SOB, and SOC. Before discussing the detailed operation of the output stepping circuit, however, it should be noted in FIG. 8 that the output conductors 0 through 9 of each counter means are connected in parallel to ten output bus conductors A through K, each of Which is coupled to a corresponding output switching relay AR through KR. Relays AR through KR each correspond to a channel A through K of tape recorder 82 (FIG. 5), and the corresponding channel is coupled to output line 77 (FIG. 6) whenever its output switching relay is energized. Thus channel A of the tape recorder 82 will `be coupled to output conductor 77 as long as relay AR is energized; channel B will be coupled to output conductor 77 as long as relay BR is energized; 'and so on.

When a train passes the hot box detector, relay AR (FIG. 8) will be energized immediately through contacts OP, and 1T1 and will seal itself closed through the relay contacts thereunder, the relay contacts under the other output relays, and contacts 5T1 and OP8. This sealing circuit is arranged so that relay AR will remain closed until time interval ST (FIG. S) when contacts ST1 open and break the sealing circuit. As long as the output stepping switches SOA, SOB, and SOC (FIG. 8) remain in their neutral (N) position, all of the output relays will remain de-energized for time intervals ST through 12T. On the following cycle of the tape recorder 82, however, relay AR will again be energized for time intervals 1T through 4T by the second closure of contacts 1T1 and the Second opening of contacts ST1. Thus, as long as the train is passing the hot box detector circuit, the message Seaboard Railroad, Riceboro, Ga. will be broadcast repeatedly on radio transmitter 73 and through the telephone lines to advise the train crew and the train dispatcher that a train is passing the hot box detector located on the Seaboard Railroad at Riceboro, Ga.

After the end of the train has passed the hot box detector, relay TP becomes de-energized and contacts TP2 (FIG. 8) and TP1 (FIG. 6) initiate the hot box readout cycle of the output circuit. The closure of back contact TP1 starts the three-minute time delay relay TD, and the closure of back contact TF2 (FIG. 8) enables output stepping motor circuit 89, which then drives the output stepping switches SOA, SOB and SOC by one increment every time contacts 12T2 close. Therefore in the 12T time period which follows the de-energization of relay TP, the output stepping switches SOA, SOB and SOC will be advanced from their neutral (N) position to their first position. Switch SOA will then read out the transverse location of the hot box, i.e., right or left side; switch SOB will read out the number of the hot box, i.e., first, second, third, or fourth; and switch SOC will enable the counter -means in turn to read out the axle count for that particular hot box. Suppose, for example, that the first hot box is located on the right hand side of tra-in 362 axles from the rear. The output sequence for this example would proeeed as follows: relay AR would be energized in the first four time intervals, as described previously, to produce the message Seaboard Railroad, rRiceboro, Ga. At the start of the fifth time interval, the sealing circuit to relay AR would be broken by the opening of contacts ST1 but a-t the same time relay AR would receive a Voltage through contacts ST2 and switch SOB. Therefore, relay AR will remain energized thorugh time interval ST to add the word first On the sixth time interval, relay AR would again be held energized by the closure of contacts 6T1 or 6T2 to add the word hot box. In the seventh time interval relay AR would drop out and relay BR would be energized through contacts 7T1 to add the word right In time interval 8T, relay BR would drop out and relay AR would be energized again through contacts 8T1 or ST2 to add the word sidef During the ninth, tenth, and eleventh time periods, voltage would be applied in time sequence to switches SIC, SlB, and S1A of counter means number l, as indicated in the circuit of FIG. 7, which would energize relays DR, GR, and CR in sequence to read out the number 362 as the axle count for the first hot box. In the twelfth time interval, contacts 12T2 close, thus driving switches SOA, SOB, and SOC to their second position. The same output sequence is then repeated except, of course, for the difference in information which depends upon the location of the second hot box. When the second hot box is read out, the word second is substituted for the word first in the readout by deenergizing relay AR and energizing relay BR at the start of the fifth time interva-l. Relay AR is de-energized by the opening of contacts ST1, and relay BR is energized by a voltage applied through contacts ST3 and switch SOB. After the second hot box has been read out, the output stepping switches would be driven to the third position to read out the location of the third hot box, and then to the fourth position to read out the location of the fourth hot box. When the third hot box is read out, the word thir is provided by energizing relay CR in the fifth time interval by mea-ns of a voltage applied through contacts ST.,A and switch SOB. For the fourth hot box, the

word fourth is provided by energizing relay DR in the fifth time interval by means of a voltage applied through contacts ST5 and switch SOB.

After all of the counters have been read out, the stepping switches will be moved back to their neutral position and will repeat the output cycle, reading out the location of each hot box in sequence for a second time. The output will continue to be repeated as long as the operating relay OP remains energized. At the end of the threeminute time delay period, however, contacts TD1 (FIG. 6) will open and the latch back circuit of relay OP will be broken by contacts 12T1 in the next 12T time interval. This turns off tape recorder 82 and initiates a reset signal in output stepping motor 89 to reset switches SOA, SOB, and SOC to their neutral (N) position and to reset all of the counter means to their zero position. This returns the entire output circuit to its original state and prepares it to examine the next train for hot boxes.

In the circuit of FIG. 8, it will be noted that output stepping motor circuit 89 operates to read out the contents of each counter means regardless of whether or not any hot boxes have been detected. In applications where this blanket readout is objectionable, however, the output stepping motor circuit of FIG. can be used to skip readout of counters which do not contain a hot box axle count. In this circuit, the stepping switches are of the spring-magnet driven type, in which the drive spring is cocked by energization of an electromagnet P and released when the electro-magnet is de-energized. When the drive spring is released, it advances the stepping switches by one position.

In the circuit of FIG. 9, a fourth output stepping switch deck SOD has been added to automatically drive the stepping switch past any counter positions which have not recorded a hot box. If the first hot box has been recorded, electromagnet P will be energized in the first time interval following the de-energization of relay TP via contacts TF3, lT2, and RR13 or LR13. Shortly after it has been energized, electromagnet P de-energizes itself via contacts P1 and advances the stepping switches from their N to their 1 position. It will be noted that the stepping switches will remain in their N position if no hot box has been recorded, thus eliminating the output stepping cycle when there is nothing to report.

If four hot boxes have been recorded, the stepping switches will be advanced by one unit in each 1T time interval, as described above, until the stepping switches are in their S position, at which time the electromagnet P will be rapidly pulsed during the next 12T time interval until it returns to the N position. The frequency of the pulses is determined by the make-break time of contacts P1, which is short enough to advance the switches through a complete cycle in one time interval. When the switches return to their N position, they will repeat the above described cycle, reporting the four hot boxes a second time and then pulsing back to the N position. When contacts 0F10 close, after the three minute reporting interval has elapsed, a reset signal will be generated by reset generator 90 when switch SOD reaches the S position.

If less than four hot boxes have been recorded, the above described pulsing operation will begin after the last recorded hot box has -been read out, due to the normally closed LR and RR contacts coupled to positions l, 2, and 3 of switch SOD. The action of these switches in advancing the pulsing cycle will be apparent to tose skilled in the art. Thus the circuit of FIG. 9 only reads out the counters which have Ibeen activated by a hot box alarm signal, and automatically skips over any counters which have not received a hot box signal. Therefore, it will be preferable to the output stepping circuit shown in FIG. 8 in many applications.

Although the above described circuits are only one example of the many suitable circuits which can be used to mechanize the invention, the particular circuits shown do have several notableadvantages. For example, in FIG.

8 it will be noted that any number of counter means can be added to the output circuit without requiring any change in the tape recorder or the output timing circuit or the output bus conductors A through K. The additional counter means would require only an additional output stepping switch position on each of the three output stepping switches SOA, SOB, and SOC. Therefore, the particular circuit shown in FIG. 8 Ihas the advantage that it can be adapted to accommodate any desired number of hot box counters with nothing more than minimal circuit alteration. In the counter circuit of FIG. 7, a minimum number of relay contacts are used to perform the output function and all of the stepping switches can be directly coupled to ten common output lines which in turn can be directly coupled to the ten common bus conductors. This circuit arrangement, which reduces the number of conductors to a minimum, is made possible by routing the output enable signals first through the output stepping switch and second through the contacts 9T, 10T, and 11T to the arm of the corresponding counter switch. In addition, the particular vocal output message generator shown in FIG. 6 and the particular sync generator and output timing means shown therein have the advantages of simplicity, reliability, accuracy, and low cost. Furthermore, it will be noted that the particular circuits shown in FIG. 6 can also be generalized to include any desired number of message channels and that the messages on the tape recorder can be easily changed to any desired form.

It should be understood, however, that this invention is by no means limited to the specific circuits disposed herein, since many modifications can be made in the circuits disclosed without departing from the basic teaching of this invention. For example, in place of the relay logic circuits shown in these drawings, solid state electronic logic circuits could be used Without affecting the fundamental operation of the invention. And although the tape recorder of this particular output circuit is operated continuously while the train is passing, it will be clear to those skilled in the art that the recorder could be operated intermittently, if desired, and also that the particular verbal sequence shown in the drawings could be changed to any other suitable sequence. Furthermore, although a frequency coded timing system is used in this particular embodiment of the invention, it will be clear that a pulse coded timing system could just as well be used in other embodiments of the invention. In addition, the stepping switches could be replaced by diode switching matrices driven by ip-op counters, if desired, and the L-R relays could be replaced by flip-Hops or any other suitable information storage device. These and many other modifications will be apparent to those skilled in the art, and this invention includes all modifications falling within the scope of the following claims.

I claim:

1. A vocal counter circuit comprising: counter means for receiving input signals and indicating the total number applied thereto; a vocal message generator comprising a plurality of message channels, equal in number to at least the numerical base of said counter, each broken into discrete time zones, each zone representing a vocal digit; means for cycling said generator channels in common, sequentially through their time zones; an output conductor; and means responsive to the count in said counter and the sequence time zone for sequentially coupling selected channels to said conductor during one complete cycling of said generator.

2. A vocal counter circuit comprising: counter means for receiving input signals and indicating the total number applied thereto; a vocal message generator comprising a plurality of message channels, equal in number to at least the numerical base of said counter, each broken into discrete time zones, each zone representing a vocal digit; means for cycling said generator channels in common sequentially through their time zones; an output conductor; means for enabling sequential counter digit orders with sequential time zones; and means responsive to the count in said counter for sequentially coupling selected channels to said conductor during one complete cycling of said generator.

3. The lvocal counter circuit claimed in claim 2 in which the numeric base is ten; the respective digit orders are units, tens, hundreds, etc., and the respective sequence time zones are N, N-l, N-Z, etc.

4. A multicounter crcuit comprising the vocal counter claimed in claim 2, further comprising means responsive to each complete cycling of said generator for coupling the next sequential counter in said vocal counter circuit.

5. The vocal counter circuit claimed in claim 2 wherein the -means for coupling selected channels to said conductor comprises a plurality of output switching elements coupled respectively between each channel and said output conductor; and in which said enabling means comprises the means for sequentially indicating the time zone position of said output message generator and means responsive to said last mentioned means for enabling each digit order in sequence.

6. The vocal counter circuit claimed in claim 2 having a plurality of said counter means comprising means for coupling each of said counter means sequentially in said vocal counter circuit; and means cooperating ywith said sequential coupling means for recycling said generator whereby each counter is vocalized sequentially.

References Cited UNITED STATES PATENTS 3/1963 Werner 179-1002 X 6/1967 Brown 23S-92 

